US swimmer Michael Phelps holds his trophy

US swimmer Michael Phelps holds his trophy

CHRISTOPHE SIMON

US swimmer Michael Phelps holds his trophy of the greatest olympic athlete of all time after he won gold in the men's 4x100m medley relay final during the swimming event at the London 2012 Olympic Games on August 4, 2012 in London. AFP PHOTO / CHRISTOPHE SIMONCHRISTOPHE SIMON/AFP/GettyImages ORG XMIT: 148073368

US swimmer Michael Phelps holds his trophy of the greatest olympic athlete of all time after he won gold in the men's 4x100m medley relay final during the swimming event at the London 2012 Olympic Games on August 4, 2012 in London. AFP PHOTO / CHRISTOPHE SIMONCHRISTOPHE SIMON/AFP/GettyImages ORG XMIT: 148073368 (CHRISTOPHE SIMON)

US swimmer Michael Phelps holds his trophy of the greatest olympic athlete of all time after he won gold in the men's 4x100m medley relay final during the swimming event at the London 2012 Olympic Games on August 4, 2012 in London. AFP PHOTO / CHRISTOPHE SIMONCHRISTOPHE SIMON/AFP/GettyImages ORG XMIT: 148073368